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典型切削机床能耗模型的研究现状及发展趋势 被引量:42
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作者 李涛 孔露露 +1 位作者 张洪潮 ASIF iqbal 《机械工程学报》 EI CAS CSCD 北大核心 2014年第7期102-111,共10页
机床作为机械制造行业的"母机",数量大、能耗高、效率低。近年来,学者们为建立精确的机床能耗模型已做大量工作。针对典型切削机床能耗的建模现状,从切削单元能耗、加工阶段整机能耗、工艺单元能耗三个层次进行综合分析。进... 机床作为机械制造行业的"母机",数量大、能耗高、效率低。近年来,学者们为建立精确的机床能耗模型已做大量工作。针对典型切削机床能耗的建模现状,从切削单元能耗、加工阶段整机能耗、工艺单元能耗三个层次进行综合分析。进而从节能优化、产品绿色性评估、企业资源配置、机床绿色设计四方面对机床能耗模型的应用进行论述。目前,机床能耗的建模逐渐面向高端数控机床,建模的目标性更加明确,与工业应用的结合也使得模型的实用价值不断提升。 展开更多
关键词 典型切削机床 切削比能 整机能耗 工艺单元能耗 节能优化
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高寒湿地和草甸退化及恢复对土壤微生物碳代谢功能多样性的影响 被引量:31
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作者 李飞 刘振恒 +10 位作者 贾甜华 李珊珊 白彦福 郭灿灿 王惟惟 孔猛 张涛 Awais iqbal 周华坤 贾宇 尚占环 《生态学报》 CAS CSCD 北大核心 2018年第17期6006-6015,共10页
为研究高寒湿地、草甸的退化及恢复与土壤微生物碳代谢功能多样性的关系,以及影响土壤微生物碳代谢功能多样性的关键因素,利用BIOLOG Eco微平板法,分析了甘肃玛曲地区5类(湿地、沼泽化草甸、高寒草甸、退化草甸、人工恢复草甸) 14个退... 为研究高寒湿地、草甸的退化及恢复与土壤微生物碳代谢功能多样性的关系,以及影响土壤微生物碳代谢功能多样性的关键因素,利用BIOLOG Eco微平板法,分析了甘肃玛曲地区5类(湿地、沼泽化草甸、高寒草甸、退化草甸、人工恢复草甸) 14个退化与恢复样地的土壤微生物对单一碳源的利用情况。结果表明,从湿地到沙化草地的逐渐退化过程中,草甸的土壤微生物群落代谢活性差异显著;主要是由于在湿地干化过程中,微生物活性逐渐升高,沼泽草甸土壤微生物活性最高;随着草甸不断退化,微生物活性逐渐降低,沙化草地最低;而人工补播恢复使土壤微生物活性有所增加,表明退化对微生物碳代谢功能多样性造成显著影响,人工恢复措施在一定程度上提高了土壤微生物活性。聚合物类(吐温40、吐温80、环状糊精、肝糖)、氨基酸类及碳水化合物类是土壤微生物主要利用的碳源。冗余分析结果显示,土壤的碳氮比、含水量、有机碳、全氮、容重、氮磷比、p H及植被覆盖度是影响土壤微生物碳代谢功能多样性的关键因子。因此,可用土壤碳代谢功能多样性变化评价高寒湿地及草甸的退化和恢复及其变化程度。 展开更多
关键词 退化草甸 微生物多样性 BIOLOG Eco微平板法 土壤理化性质 植被
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Survey of intrusion detection systems:techniques,datasets and challenges 被引量:28
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作者 Ansam Khraisat iqbal Gondal +1 位作者 Peter Vamplew Joarder Kamruzzaman 《Cybersecurity》 CSCD 2019年第1期1-22,共22页
Cyber-attacks are becoming more sophisticated and thereby presenting increasing challenges in accurately detecting intrusions.Failure to prevent the intrusions could degrade the credibility of security services,e.g.da... Cyber-attacks are becoming more sophisticated and thereby presenting increasing challenges in accurately detecting intrusions.Failure to prevent the intrusions could degrade the credibility of security services,e.g.data confidentiality,integrity,and availability.Numerous intrusion detection methods have been proposed in the literature to tackle computer security threats,which can be broadly classified into Signature-based Intrusion Detection Systems(SIDS)and Anomaly-based Intrusion Detection Systems(AIDS).This survey paper presents a taxonomy of contemporary IDS,a comprehensive review of notable recent works,and an overview of the datasets commonly used for evaluation purposes.It also presents evasion techniques used by attackers to avoid detection and discusses future research challenges to counter such techniques so as to make computer systems more secure. 展开更多
关键词 MALWARE Intrusion detection system NSL_KDD Anomaly detection Machine learning
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Phytoremediation of heavy metal polluted soils and water:Progresses and perspectives 被引量:27
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作者 Mohammad iqbal LONE Zhen-li HE +1 位作者 Peter J. STOFFELLA Xiao-e YANG 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2008年第3期210-220,共11页
Environmental pollution affects the quality of pedosphere,hydrosphere,atmosphere,lithosphere and biosphere.Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil ... Environmental pollution affects the quality of pedosphere,hydrosphere,atmosphere,lithosphere and biosphere.Great efforts have been made in the last two decades to reduce pollution sources and remedy the polluted soil and water resources.Phytoremediation,being more cost-effective and fewer side effects than physical and chemical approaches,has gained increasing popularity in both academic and practical circles.More than 400 plant species have been identified to have potential for soil and water remediation.Among them,Thlaspi,Brassica,Sedum alfredii H.,and Arabidopsis species have been mostly studied.It is also expected that recent advances in biotechnology will play a promising role in the development of new hyperaccumulators by transferring metal hyperaccumulating genes from low biomass wild species to the higher biomass producing cultivated species in the times to come.This paper attempted to provide a brief review on recent progresses in research and practical applications of phytoremediation for soil and water resources. 展开更多
关键词 Environmental pollution Heavy metals PHYTOREMEDIATION SOIL WATER
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Biosorption characteristics of unicellular green alga Chlorella sorokiniana immobilized in loofa sponge for removal of Cr(Ⅲ) 被引量:20
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作者 AKHTAR Nasreen iqbal Muhammad +1 位作者 ZAFAR Saeed iqbal iqbal Javed 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2008年第2期231-239,共9页
Loofa sponge (LS) immobilized biomass of Chlorella sorokiniana (LSIBCS), isolated from industrial wastewater, was investigated as a new biosorbent for the removal of Cr(Ⅲ) from aqueous solution. A comparison of... Loofa sponge (LS) immobilized biomass of Chlorella sorokiniana (LSIBCS), isolated from industrial wastewater, was investigated as a new biosorbent for the removal of Cr(Ⅲ) from aqueous solution. A comparison of the biosorption of Cr(Ⅲ) by LSIBCS and free biomass of C. sorokiniana (FBCS) from 10-300 mg Cr(Ⅲ)/L aqueous solutions showed an increase in uptake of 17.79% when the microalgal biomass was immobilized onto loofa sponge. Maximum biosorption capacity for LSIBCS and FBCS was found to be 69.26 and 58.80 mg Cr(Ⅲ)/g biosorbent, respectively, whereas the amount of Cr(Ⅲ) ions adsorbed onto naked LS was 4.97 mg/g. The kinetics of Cr(Ⅲ) biosorption was extremely rapid and equilibrium was established in about 15 and 20 min by LSIBCS and FBCS, respectively. The biosorption equilibrium was well defined by Langmuir adsorption isotherm model. The biosorption kinetics followed the pseudo-second order kinetic model. The biosorption was found to be pH dependent and the maximum sorption occurred at the solution pH 4.0. Desorption studies showed that 98% of the adsorbed Cr(Ⅲ) could be desorbed with 0.1 mol/L HNO3, while other desorbing agents were less effective in the order: EDTA 〉 H2SO4 〉 CH3COOH 〉 HCl. The regenerated LSIBCS retained 92.68% of the initial Cr(Ⅲ) binding capacity up to five cycles of reuse in continuous flow-fixed bed columns. The study revealed that LSIBCS could be used as an effective biosorbent for the removal of Cr(Ⅲ) from wastewater. 展开更多
关键词 BIOSORPTION immobilization loofa sponge Chlorella sorokiniana Cr(Ⅲ) DESORPTION fixed bed column reactor
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青少年性相关知识来源的偏好:中国性教育的启示 被引量:22
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作者 张立英 iqbal H.Shah +4 位作者 李晓铭 尹文强 傅继华 夏志森 Bonita Stanton 《国际生殖健康/计划生育杂志》 CAS 2010年第6期422-428,433,共8页
目的:探讨分析15~24岁年龄段青少年性教育来源的偏好。方法:本研究所使用的数据来自于一项由世界卫生组织(WHO)资助的项目(WHO第98200号项目)。此项目是在中国东北某城市实施的基于社区为基础的横断面调查。住户样本的抽取采用按规模... 目的:探讨分析15~24岁年龄段青少年性教育来源的偏好。方法:本研究所使用的数据来自于一项由世界卫生组织(WHO)资助的项目(WHO第98200号项目)。此项目是在中国东北某城市实施的基于社区为基础的横断面调查。住户样本的抽取采用按规模大小成比例的概率抽样原则,进行3阶段系统抽样设计。共有1319名15~24岁的青少年接受调查,并在参与调查前签署了知情同意书,参与者被告知自愿参加并有权退出调查和跳过其不愿回答的问题。最终有1227条记录进入分析阶段。运用描述性统计和多元Logistic回归分析方法对青少年获取性相关知识的来源偏好和实际获得知识的来源之间的差异进行分析。结果:青少年在过去实际使用的知识来源和其对来源的偏好方面存在差异。"父母","医生","书籍和报纸"和"电视"未能发挥青少年所预期的作用。青少年倾向于将"医生"作为获得"青春期"、"性知识"及"性传播疾病/艾滋病"等知识的主要渠道,而实际使用与来源偏好方面大概有10.2%~11.0%的差距。实际来自于父母对孩子的性教育则比偏好约低0.1%~2.7%。"书籍和报纸"和"电视"作为获得性相关知识的实际来源比偏好低3.3%~7.5%。多因素Logistic回归分析结果显示,年龄、性别、教育水平、工作经历和有无兄弟姐妹等因素影响青少年对获取性知识来源的偏好。20~24岁的男性更倾向于将"电视"作为其获取青春期知识的首选来源(回归系数=0.408,P<0.05),而女性则不倾向于将"电视"作为其首选来源去获取青春期知识、性知识和性传播疾病/艾滋病知识(回归系数分别为-1.305,-0.989和-0.653,P<0.05或P<0.01)。受过大学或研究生教育的被调查者不倾向将"老师"作为首选来源去获取青春期知识及性知识(回归系数分别为-0.544和-0.638,P<0.05)。相对于没有工作经历的被调查者,有工作经历的被调查者更倾向于将"� 展开更多
关键词 青少年 性教育 获得性免疫缺陷综合征 性传播疾病 数据收集
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Role of a probiotic (Saccharomyces boulardii) in management and prevention of diarrhoea 被引量:22
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作者 AG Billoo MA Memon +4 位作者 SA Khaskheli G Murtaza Khalid iqbal M Saeed Shekhani Ahson Q Siddiqi 《World Journal of Gastroenterology》 SCIE CAS CSCD 2006年第28期4557-4560,共4页
AIM: To assess the efficacy and safety of Saccharomyces boulardii (S. boulardii) in acute watery diarrhoea and its role in reducing the frequency of episodes of diarrhoea in subsequent two months. METHODS: Childre... AIM: To assess the efficacy and safety of Saccharomyces boulardii (S. boulardii) in acute watery diarrhoea and its role in reducing the frequency of episodes of diarrhoea in subsequent two months. METHODS: Children from 2 mo to 12 years of age, with acute diarrhoea were selected according to inclusion criteria and randomised in S. boulardii group (treated with ORS, nutritional support and S. boulardii, 250 mg bid) and in control group (treated with ORS and nutritional support only). Active treatment phase was 5 d and each child was followed for two months afterwards. Frequency and consistency of stools as well as safety of drug was assessed on every visit. A comparison of two groups was done in terms of number of diarrhoeal episode in subsequent two months. RESULTS: There were fifty patients in each group. Baseline characteristics such as mean age and the average frequency of stools were comparable in S. boulardii and control group at the time of inclusion in the trial. By d 3 it reduced to 2.7 and 4.2 stools per d respectively and by d 6 it reduced to 1.6 (5. boulardii Group) and 3.3 (control group). The duration of diarrhoea was 3.6 d in S. boulardii group whereas it was 4.8 d in control group (P = 0.001). In the following two months, S. boulardii group had a significantly lower frequency of 0.54 episodes as compared to 1.08 episodes in control group. The drug was well accepted and tolerated. There were no reports of the side effects during treatment period CONCLUSION: S. boulardii significantly reduces the frequency and duration of acute diarrhoea. The consistency of stool also improves. The drug is well-tolerated. 展开更多
关键词 Acute watery diarrhoea Probiotic Saccharomyces boulardii Frequency of episodes of diarrhoea Weight gain
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Cadmium Toxicity in Plants and Role of Mineral Nutrients in Its Alleviation 被引量:19
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作者 Rahat Nazar Noushina iqbal +3 位作者 Asim Masood M. iqbal R. Khan Shabina Syeed Nafees A. Khan 《American Journal of Plant Sciences》 2012年第10期1476-1489,共14页
Cadmium (Cd) is a toxic heavy metal that enters the environment through various anthropogenic sources, and inhibits plant growth and development. Cadmium toxicity may result from disturbance in plant metabolism as a c... Cadmium (Cd) is a toxic heavy metal that enters the environment through various anthropogenic sources, and inhibits plant growth and development. Cadmium toxicity may result from disturbance in plant metabolism as a consequence of disturbance in the uptake and translocation of mineral nutrients. Plant nutrients and Cd compete for the same transporters and, therefore, presence of Cd results in mineral nutrients deficiency. The optimization of mineral nutrients under Cd stress could reduce Cd toxicity by greater availability at the transport site resulting in reduced accumulation of Cd, and could also alleviate Cd-induced toxic effects by enhancing biochemical reactions and physiological processes in plants. In the present review the role of plant macro, micro and beneficial elements in alleviating Cd stress in crop plants is discussed. 展开更多
关键词 ANTIOXIDANT ENZYMES Cadmium TOXICITY MINERAL NUTRITION OXIDATIVE Stress
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Landslide susceptibility mapping using an integrated model of information value method and logistic regression in the Bailongjiang watershed,Gansu Province,China 被引量:19
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作者 DU Guo-liang ZHANG Yong-shuang +2 位作者 iqbal Javed YANG Zhi-hua YAO Xin 《Journal of Mountain Science》 SCIE CSCD 2017年第2期249-268,共20页
Bailongjiang watershed in southern Gansu province, China, is one of the most landslide-prone regions in China, characterized by very high frequency of landslide occurrence. In order to predict the landslide occurrence... Bailongjiang watershed in southern Gansu province, China, is one of the most landslide-prone regions in China, characterized by very high frequency of landslide occurrence. In order to predict the landslide occurrence, a comprehensive map of landslide susceptibility is required which may be significantly helpful in reducing loss of property and human life. In this study, an integrated model of information value method and logistic regression is proposed by using their merits at maximum and overcoming their weaknesses, which may enhance precision and accuracy of landslide susceptibility assessment. A detailed and reliable landslide inventory with 1587 landslides was prepared and randomly divided into two groups,(i) training dataset and(ii) testing dataset. Eight distinct landslide conditioning factors including lithology, slope gradient, aspect, elevation, distance to drainages,distance to faults, distance to roads and vegetation coverage were selected for landslide susceptibility mapping. The produced landslide susceptibility maps were validated by the success rate and prediction rate curves. The validation results show that the success rate and the prediction rate of the integrated model are 81.7 % and 84.6 %, respectively, which indicate that the proposed integrated method is reliable to produce an accurate landslide susceptibility map and the results may be used for landslides management and mitigation. 展开更多
关键词 Landslide susceptibility Integrated model Information value method Logistic regression Bailongjiang watershed
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趋化性细胞因子受体CXCR4在大肠癌的表达及其临床意义 被引量:13
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作者 张孟贤 Kashif iqbal 于世英 《世界华人消化杂志》 CAS 北大核心 2007年第7期772-776,共5页
目的:探讨趋化性细胞因子受体CXCR4在大肠癌中的表达及其与预后的关系.方法:收集67例大肠癌患者手术标本,采用免疫组织化学方法检测肿瘤组织中CXCR4蛋白的表达和微血管密度,分析CXCR4的表达水平与临床病理特征和生存的关系.结果:大肠癌... 目的:探讨趋化性细胞因子受体CXCR4在大肠癌中的表达及其与预后的关系.方法:收集67例大肠癌患者手术标本,采用免疫组织化学方法检测肿瘤组织中CXCR4蛋白的表达和微血管密度,分析CXCR4的表达水平与临床病理特征和生存的关系.结果:大肠癌组织中CXCR4蛋白表达阳性率为56.7%(38/67),与患者的性别、年龄、肿瘤部位、T分期和病理类型无相关性(P>0.05),与淋巴结转移、临床分期、微血管密及生存相关.N0,N1和N2期CXCR4的阳性率分别为40.6%,68.2%,76.9%(P<0.05);Ⅰ+Ⅱ期和Ⅲ期CXCR4的阳性率分别为39.4%,73.5%(P<0.05).低MVD组CXCR4的阳性率显著低于高MVD组(36.4%vs74.3%,P<0.01);CXCR4阳性组较CXCR4阴性组有较高的复发/转移率(47.4%vs24.1%,P<0.05)和较低的3a无病生存率(32.6%vs71.3%,P<0.05).结论:CXCR4可能促进大肠癌的侵袭和转移以及血管生成并影响其预后. 展开更多
关键词 CXCR4蛋白 大肠癌 微血管密度 预后
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Zinc-doped hydroxyapatite-zeolite/polycaprolactone composites coating on magnesium substrate for enhancing in-vitro corrosion and antibacterial performance 被引量:11
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作者 Nida iqbal Saman iqbal +6 位作者 Tanveer iqbal H.R.BAKHSHESHI-RAD Ahmed ALSAKKAF Ahmad KAMIL Mohammed Rafiq ABDUL KADIR Mohd Hasbullah IDRIS H.Balaji RAGHAV 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2020年第1期123-133,共11页
This work is focused on developing zinc-doped hydroxyapatite-zeolite(Zn HA-Zeo)and polycaprolactone(PCL)composite coatings on magnesium(Mg)substrate to improve the corrosion resistance and antimicrobial properties.Dip... This work is focused on developing zinc-doped hydroxyapatite-zeolite(Zn HA-Zeo)and polycaprolactone(PCL)composite coatings on magnesium(Mg)substrate to improve the corrosion resistance and antimicrobial properties.Dip-coating technique was used to coat Zn HA-Zeo/PCL on the Mg substrate at room temperature.The samples were subjected to field emission scanning electron microscopy(FESEM),X-ray diffraction(XRD),Fourier transform infrared(FTIR),energy dispersive X-ray spectroscopy(EDX)and antimicrobial potential.Results demonstrated that composite coatings consist of HA,scholzite,zeolite,and PCL phases.EDX spectra indicated the presence of calcium(Ca),silicon(Si),aluminum(Al),zinc(Zn),phosphorus(P)and oxygen(O).The composite surface appeared in spherical-like microstructure on coating with thickness ranging 226-260μm.Zinc-doped HA-Zeo composite coating had a high corrosion resistance and provided sufficient protection to the Mg surface against galvanic corrosion.Doped Zn HA-Zeo coating samples exhibited superior disc inhibition by confirming antimicrobial activity against the E.coli as compared to HA-Zeo sample.Altogether these results showed that the Zn HA-Zeo coatings not only improved the corrosion resistance,but also enhanced the antimicrobial property and hence they can be used as suitable candidates for implant applications. 展开更多
关键词 biodegradable magnesium bioceramics coating corrosion resistance antimicrobial activity
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Comparative analysis of the complete chloroplast genome among Prunus mume,P.armeniaca,and P.salicina 被引量:14
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作者 Song Xue Ting Shi +7 位作者 Wenjie Luo Xiaopeng Ni Shahid iqbal Zhaojun Ni Xiao Huang Dan Yao Zhijun Shen Zhihong Gao 《Horticulture Research》 SCIE 2019年第1期626-638,共13页
Prunus mume Sieb.et Zucc.,P.armeniaca L.,and P.salicina L.are economically important fruit trees in temperate regions.These species are taxonomically perplexing because of shared interspecific morphological traits and... Prunus mume Sieb.et Zucc.,P.armeniaca L.,and P.salicina L.are economically important fruit trees in temperate regions.These species are taxonomically perplexing because of shared interspecific morphological traits and variation,which are mainly attributed to hybridization.The chloroplast is cytoplasmically inherited and often used for evolutionary studies.We sequenced the complete chloroplast genomes of P.mume,P.armeniaca,and P.salicina using Illumina sequencing followed by de novo assembly.The three chloroplast genomes exhibit a typical quadripartite structure with conserved genome arrangement,structure,and moderate divergence.The lengths of the genomes are 157,815,157,797,and 157,916 bp,respectively.The length of the large single-copy region(LSC)region is 86,113,86,283,and 86,122 bp,and the length of the SSC region is 18,916,18,734,and 19,028 bp;the IR region is 26,393,26,390,and 26,383 bp,respectively.Each of the three chloroplast genomes encodes 133 genes,including 94 protein-coding,31 tRNA,and eight rRNA genes.Differential gene analysis for the three species revealed that trnY-ATA is a unique gene in P.armeniaca;in contrast,the gene trnI-TAT is only present in P.mume and P.salicina,though the position of the gene in these chloroplast genomes differs.Further comparative analysis of the complete chloroplast genome sequences revealed that the ORF genes and the sequences of linked regions rps16 and atpA,atpH and atpI,trnc-GCA and psbD,ycf3 and atpB,and rpL32 and ndhD are significantly different and may be used as molecular markers in taxonomic studies.Phylogenetic evolution analysis of the three species suggests that P.mume has a closer genetic relationship to P.armeniaca than to P.salicina. 展开更多
关键词 RRNA TRAITS analysis
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Impact of on-range choice feeding with black soldier fly larvae(Hermetia illucens)on flock performance,egg quality,and range use of free-range laying hens 被引量:14
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作者 Isabelle Ruhnke Camille Normant +4 位作者 Dana L.M.Campbell Zafar iqbal Caroline Lee Geoff N.Hinch Julie Roberts 《Animal Nutrition》 2018年第4期452-460,共9页
Semi-intensive free-range farm systems are common in Australia, and these systems frequently practise on-range feeding. The objective of this study was to investigate the benefit of on-range choice feeding on flock pe... Semi-intensive free-range farm systems are common in Australia, and these systems frequently practise on-range feeding. The objective of this study was to investigate the benefit of on-range choice feeding on flock performance, egg quality, and range use of free-range laying hens using black soldier fly larvae(Hermetia illucens, BSF). A total of 160 mature ISA brown laying hens, previously determined to range daily, were allocated to a control group(control) or a treatment group(BSF) with various replicates depending on the parameter investigated. All hens were fed ad libitum indoors with a wheat-soy based diet formulated according to breed requirements. Black soldier fly hens were offered dried BSF larvae ad libitum on the range. Body weight, feed intake, BSF intake, egg production, feed conversion ratio, internal and external egg quality parameters, and individual range use using radio-frequency identification(RFID)technology was evaluated. Black soldier fly hens consumed on average 15 ± 1.7 g BSF larvae/hen per day.There were no differences between BSF and control hens for any of the performance parameters obtained(P > 0.05). Egg weight, shell weight, and shell thickness of eggs from BSF hens were significantly lower(P = 0.003, P = 0.001, and P = 0.004, respectively) than those of eggs from control hens. Egg yolk colour was significantly paler in eggs from BSF hens(P < 0.001). No significant ranging differences between the BSF and control hens were observed(P > 0.05) except for BSF hens showing longer total maximum time for a single visit to the range(P = 0.011). In conclusion, the average intake of BSF larvae indicated a good level of acceptance. Feed formulation should be adjusted for the intake of the choice fed source. The impact of choice-feeding on range use was minor. 展开更多
关键词 Behaviour Chicken Insect protein Nutrition POULTRY Radio-frequency identification
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Increased hepcidin expression in colorectal carcinogenesis 被引量:12
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作者 Douglas G Ward Keith Roberts +6 位作者 Matthew J Brookes Howard Joy Ashley Martin Tariq Ismail Robert Spychal Tariq iqbal Chris Tselepis 《World Journal of Gastroenterology》 SCIE CAS CSCD 2008年第9期1339-1345,共7页
AIM:To investigate whether the iron stores regulator hepcidin is implicated in colon cancer-associated anae- mia and whether it might have a role in colorectal car- cinogenesis. METHODS: Mass spectrometry (MALDI-TOF M... AIM:To investigate whether the iron stores regulator hepcidin is implicated in colon cancer-associated anae- mia and whether it might have a role in colorectal car- cinogenesis. METHODS: Mass spectrometry (MALDI-TOF MS and SELDI-TOF MS) was employed to measure hepcidin in urine collected from 56 patients with colorectal cancer. Quantitative Real Time RT-PCR was utilised to determine hepcidin mRNA expression in colorectal cancer tissue. Hepcidin cellular localisation was determined using im- munohistochemistry. RESULTS: We demonstrate that whilst urinary hepcidin expression was not correlated with anaemia it was posi- tively associated with increasing T-stage of colorectal cancer (P < 0.05). Furthermore, we report that hepcidin mRNA is expressed in 34% of colorectal cancer tissue specimens and was correlated with ferroportin repres- sion. This was supported by hepcidin immunoreactivity in colorectal cancer tissue. CONCLUSION: We demonstrate that systemic hepcidin expression is unlikely to be the cause of the systemic anaemia associated with colorectal cancer. However, we demonstrate for the first time that hepcidin is expressed by colorectal cancer tissue and that this may represent a novel oncogenic signalling mechanism. 展开更多
关键词 IRON HEPCIDIN COLON Cancer ANAEMIA Mass spectrometry
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Methane hydrate formation and dissociation in synthetic seawater 被引量:12
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作者 Vikash Kumar Saw iqbal Ahmad +2 位作者 Ajay Mandal G.Udayabhanu Sukumar Laik 《Journal of Natural Gas Chemistry》 EI CAS CSCD 2012年第6期625-632,共8页
The formation and dissociation of methane gas hydrate at an interface between synthetic seawater (SSW) and methane gas have been experimentally investigated in the present work. The amount of gas consumed during hyd... The formation and dissociation of methane gas hydrate at an interface between synthetic seawater (SSW) and methane gas have been experimentally investigated in the present work. The amount of gas consumed during hydrate formation has been calculated using the real gas equation. Induction time for the formation of hydrate is found to depend on the degree of subcooling. All the experiments were conducted in quiescent system with initial cell pressure of 11.14 MPa. Salinity effects on the onset pressure and temperature of hydrate formation are also observed. The dissociation enthalpies of methane hydrate in synthetic seawater were determined by Clausius-Clapeyron equation based on the measured phase equilibrium data. The dissociation data have been analyzed by existing models and compared with the reported data. 展开更多
关键词 methane hydrate formation and dissociation total dissolved salt induction time SUBCOOLING
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NAFLD Epidemiology, Emerging Pharmacotherapy, Liver Transplantation Implications and the Trends in the United States 被引量:12
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作者 Chiranjeevi Gadiparthi Moshe Spatz +5 位作者 Simi Greenberg Umair iqbal Sowjanya Kanna Sanjaya K Satapathy Arkady Broder Aijaz Ahmed 《Journal of Clinical and Translational Hepatology》 SCIE 2020年第2期215-221,共7页
Nonalcoholic fatty liver disease (NAFLD) is a hepatic mani-festation of metabolic syndrome. The spread of obesity worldwide in pandemic proportions has led to a rapid rise of NAFLD in developed and developing countrie... Nonalcoholic fatty liver disease (NAFLD) is a hepatic mani-festation of metabolic syndrome. The spread of obesity worldwide in pandemic proportions has led to a rapid rise of NAFLD in developed and developing countries alike. There are no approved pharmacological agents to treat steatohepatitis or advanced fibrosis but obeticholic acid recently has shown some promise in phase III trial. Currently, NAFLD is the number one etiology for simultaneous liver and kidney trans-plantation in the USA, second most common indication for liver transplantation (LT) and projected to become number one very soon. LT for NAFLD poses unique challenges, as these patients are generally older, obese and more likely to have a number of metabolic risk factors. Bariatric surgery is an option and can be considered if a structured weight loss program does not achieve the sustained weight loss goal. Comprehensive cardiovascular risk assessment and aggres-sive management of comorbid conditions are crucial in the LT evaluation process to improve post-transplant survival. Re-current nonalcoholic steatohepatitis after LT is not uncom-mon, and thus warrants primary and secondary prevention strategies through a multidisciplinary approach. Prevalence of NAFLD in a donor population is a unique and growing concern that limits the access to quality liver grafts. 展开更多
关键词 NAFLD NAFL NASH Liver transplantation
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Adjuvant effects of saponins on animal immune responses 被引量:9
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作者 RAJPUT Zahid iqbal ARIJO Abdullah G. 《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》 SCIE CAS CSCD 2007年第3期153-161,共9页
Vaccines require optimal adjuvants including immunopotentiator and delivery systems to offer long term protection from infectious diseases in animals and man. Initially it was believed that adjuvants are responsible f... Vaccines require optimal adjuvants including immunopotentiator and delivery systems to offer long term protection from infectious diseases in animals and man. Initially it was believed that adjuvants are responsible for promoting strong and sustainable antibody responses. Now it has been shown that adjuvants influence the isotype and avidity of antibody and also affect the properties of cell-mediated immunity. Mostly oil emulsions, lipopolysaccharides, polymers, saponins, liposomes, cytokines, ISCOMs (immunostimulating complexes), Freund’s complete adjuvant, Freund’s incomplete adjuvant, alums, bacterial toxins etc., are common adjuvants under investigation. Saponin based adjuvants have the ability to stimulate the cell mediated immune system as well as to enhance antibody production and have the advantage that only a low dose is needed for adjuvant activity. In the present study the importance of adjuvants, their role and the effect of saponin in immune system is reviewed. 展开更多
关键词 ADJUVANTS SAPONINS IMMUNITY Immunostimulators STEROIDS TRITERPENOID
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In vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah 被引量:11
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作者 M Amzad Hossain Muhammad Dawood Shah +1 位作者 Charles Gnanaraj Muhammad iqbal 《Asian Pacific Journal of Tropical Medicine》 SCIE CAS 2011年第9期717-721,共5页
Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dr... Objective:To detect the in vitro total phenolics,flavonoids contents and antioxidant activity of essential oil,various organic extracts from the leaves of tropical medicinal plant Tetrastigma from Sabah.Methods:The dry powder leaves of Tetrastigma were extracted with different organic solvent such as hexane.ethyl acetate,chloroform,butanol and aqueous methanol.The total phenolic and total flavonoids contents of the essential oil and various organic extracts such as hexane,ethyl acetate,chloroform,butanol and aqueous ethanol were determined by Folin-Ciocalteu method and the assayed antioxidant activity was determined in vitro models such as antioxidant capacity by radical scavenging activity usingα,α-diphenyl-β-picrylhydrazyl (DPPH) method.Results:The total phenolic contents of the essential oil and different extracts as gallic acid equivalents were found to be highest in methanol extract(386.22 mg/g) followed by ethyl acetate(190.89 mg/g).chloroform(175.89 mg/g).hexane(173.44 mg/g).and Imtanol extract (131.72 mg/g) and the phenolic contents not detected in essential oil.The antioxidant capacity of the essential oil and different extracts as ascorbic acid standard was in the order of methanol extract】ethyl acetate extract】chloroform】butanol】hexane extract also the antioxidant activity was not detected in essential oil.Conclusions:The findings show that the extent of antioxidant activity of the essential oil and all extracts are in accordance with the amount of phenolics present in that extract.Leaves of Tetrastigma being rich in phenolics may provide a good source of antioxidant. 展开更多
关键词 Total phenolics FLAVONOIDS Antioxidant aotivity Essential oil EXTRACTS Tetrastigma
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Lithium-ion full cell with high energy density using nickel-rich LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode and SiO-C composite anode 被引量:11
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作者 Azhar iqbal Long Chen +3 位作者 Yong Chen Yu-xian Gao Fang Chen Dao-cong Li 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2018年第12期1473-1481,共9页
A high-energy-density Li-ion battery with excellent rate capability and long cycle life was fabricated with a Ni-rich layered LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode and Si O-C composite anode. The LiNi_(0.8)Co_(0.1)Mn_... A high-energy-density Li-ion battery with excellent rate capability and long cycle life was fabricated with a Ni-rich layered LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 cathode and Si O-C composite anode. The LiNi_(0.8)Co_(0.1)Mn_(0.1)O_2 and Si O-C exhibited excellent electrochemical performance in both half and full cells. Specifically, when integrated into a full cell configuration, a high energy density(280 Wh·kg^(-1)) with excellent rate capability and long cycle life was attained. At 0.5 C, the full cell retained 80% of its initial capacity after 200 charge/discharge cycles, and 60% after 600 cycles, indicating robust structural tolerance for the repeated insertion/extraction of Li^+ ions. The rate performance showed that, at high rate of 1 C and 2 C, 96.8% and 93% of the initial capacity were retained, respectively. The results demonstrate strong potential for the development of high energy density Li-ion batteries for practical applications. 展开更多
关键词 HIGH energy DENSITY full cell rate performance HIGH capacity CATHODE
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基于改进变分模态分解去噪的高频电应力下聚酰亚胺局部放电温-频特性研究 被引量:4
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作者 徐黄宽 张黎 +2 位作者 Bilal iqbal Ayubi 邹亮 王冠 《电工技术学报》 EI CSCD 北大核心 2023年第3期565-576,共12页
局部放电是导致高频电力变压器中聚酰亚胺(PI)绝缘劣化的重要原因。为研究高频电压下聚酰亚胺局部放电机理,探索温度、频率因素对局部放电特性的影响,建立了高频局部放电测试平台。针对使用脉冲电流传感器采集局部放电信号容易受噪声干... 局部放电是导致高频电力变压器中聚酰亚胺(PI)绝缘劣化的重要原因。为研究高频电压下聚酰亚胺局部放电机理,探索温度、频率因素对局部放电特性的影响,建立了高频局部放电测试平台。针对使用脉冲电流传感器采集局部放电信号容易受噪声干扰的问题,采用变分模态分解(VMD)对局部放电原始信号进行去噪。其中,针对VMD难以自适应选取分解参数的问题,使用平衡优化器(EO)算法获得最优模态分解个数K与惩罚因子α。实验获取了25~100℃四个温度点与10~50kHz五个频率点下的聚酰亚胺局部放电情况,并分析其变化规律。实验结果表明,温度越大放电起始电压越小,而频率与局部放电起始电压无关;最大放电幅值、总放电幅值和单周波平均放电次数与温度、频率呈正相关;频率越高,温度对局部放电特征量的影响越大,而温度越高,频率对局部放电特征量的影响也更为显著,两者呈现一种耦合促进关系。 展开更多
关键词 局部放电 平衡优化器 变分模态分解 温度 频率 聚酰亚胺
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